Moving Landmesses in Messosoic Era : Geography

The design of how to navigate on this page is really clear, and very easy to understand, until many friends and fans admire it. This page has a time line which is not divided with the correct lenght, but it is divided with a proper lenght to explain the first year and the last year of each period in Mesozoic ear. The user would move his mouse around the page, and the image of earth will follow his mouse in X direction. The landmasses in the image of the earth will keep changing along the position on the timeline, as well as the name of each period.

After I finished this animation of moving landmasses, I put it in a movie clip, and I calculate the length of timeline comparing with the length of the time in movie clip.

Triassic Landmasses (250-206 Million Years Ago)

Jurassic Landmasses (206-144 Million Years Ago)

Cretaceous Landmasses (144-65 Million Years Ago)

Current Landmasses

Additional Idea of Inbetween image.
When I made this, I have 4 key drawing which are Triassic landmasses, Jurassic landmasses, Cretaceous landmasses and current landmasses. I drew the drawing inbetween 7 drawing for each. This means I kept drawing the inbetween image 4 times.

First time I have 4 drawing
Second, I draw inbetween images, I have 7 drawings
Third, I draw inbetween images, I have 13 drawings
Forth, I draw inbetween images, I have 25 drawings

If I have 1 key drawing, and I draw 1 time, all drawing equals 1.
If I have 2 key drawing, and I draw 2 times, all drawing equals 3.
If I have 3 key drawing, and I draw 3 times, all drawing equals 9.
If I have 4 key drawing, and I draw 4 times, all drawing equals 25.
If I have 5 key drawing, and I draw 5 times, all drawing equals 65.
If I have 6 key drawing, and I draw 6 times, all drawing equals 161.

This is just like Cullen series, which is 1,3,9,25,65,161,…
This is the formular n x (2^n) + 1

**Thanks Simple Nobody and Kittisak Kaweekijmanee for the formular; because I came up with this serie with the step-by-step calculation, which is I ran the program, for(i=0 ; i<inc; i++){ trace(inc*2 -1);}.